Blessington, historically known as Ballycomeen[1] (Irish: Baile Coimín, meaning "town of Comyn", from the Irish surname Ó Coimín), is a town on the River Liffey in Wicklow, Ireland, near the border with Kildare. It is around 25 km south-west of Dublin, and is situated on the N81 road which connects Dublin to Tullow.

Since 2000, Blessington's population has increased substantially, at 5,010 at the 2011 census CSO, up from 2,509 in 2000. The majority of housing estates were constructed on the western side of the town, off the R410, which is the road to Naas.

A new inner bypass has also been opened that alleviates traffic on Main Street to some degree.

In 2006, two new schools were established,
- Gaelscoil na Lochanna (School of the Lakes) was founded to cater for those in Blessington and the surrounding area who wished to educate their children primarily through the Irish language. The school was sited initially on the grounds of the Community Education Centre, with a plan to move to a green field site on the Kilmalum road in 2009.
- Educate Together established a new national school in the town, founded on the site of a long-standing school and benefitting from a large sports field.

These new schools supplement the existing primary schools in the town: Saint Mary's National School, and the Number One school (Church of Ireland). A new building has been built across the road from the original Saint Mary's school, in order to alleviate overcrowding and the Number One school moved into a new building in 2008. St. Mary's Junior National School (J.N.S.) accommodates students from Junior infants to second class and St. Mary's Senior National School (S.N.S.) accommodates students from 3rd Classs to 6th Class.

There is also a Community College on the Naas Road, which currently has an enrolment of over 300 students with growing numbers predicted in the immediate future.

A new library was also opened at the end of 2006 on the first floor of the new town centre building, above the anchor tenant, Dunnes Stores.

In 1888, the Dublin and Blessington Steam Tramway service commenced from Terenure to Blessington via Tallaght, linking with the horse trams from the city.[5] This service ended at the end of December 1932 and was replaced with a conventional bus service, the 65, which still acts as the only public transport in the area to the city centre. Bus Éireann, the national bus company, also provides a minor service, because Blessington is upon the N81. The R410 is another major road that connects Blessington with Naas. The route starts in the south end of the town heading west and proceeds up over the hills of Glending Forest and Eadestown. The road terminates in the Eastside of Naas as the Blessington Road. During the winter months the route is very treacherous during heavy snowfall and is sometimes closed in severe conditions.

Also known locally as the Blessington Lake, the reservoir was created when the waterfall at Poulaphouca on the River Liffey (which flows from the Wicklow Mountains to Dublin) was dammed by the ESB for a hydroelectric plant which is still in use today. The valley was flooded and the resulting lakes extend over approximately 5,000 acres (2,023 ha). A small village was submerged by the damming of the waterfall, and the remains of roads can still be seen leading down into the lake.

In addition to electricity, the lakes also provide water for the locality and the Dublin region as well as provide a leisure resource. There is now a lakeside luxury hotel complex in the Blessington area, with its own helipad, and lakeside facilities which has helped to develop tourism in the area. The lake is also extensively used by boatmen and fishermen, and is a training location for the Irish Air Corps HQ divisions from Baldonnel, 15 km north of Blessington, and also Local Civil Defence Water rescue teams.